http://www.GermanCarScene.com/ V10-Powered Audi R8 spotted. If you don't believe that the engine's a V10 unit, check here for pictures: http://germancarscene.com/2008/05/14/v10-powered-audi-r8-spotted/
Impressive video featuring Hartge's H50 V10 model which is equipped with a tuned 5.0 V10 M5 engine producing 550 Hp
See the coupe version here:
http://carscoop.blogspot.com/2006/12/hartge-h50-v10-coupe-bmw-3-series.html